Abstract head of the substitution group for groups whose members are observationsystems: ground models, logs and other interpreted characterizations. A member joinsby carrying diggs:observationGroupRef, declared ondiggs:AbstractObservationSystemType. No concrete type substitutes this head yet.Several observation systems may be meaningful only when read together, for exampletwo ground models of the same site built on different assumptions, or logs that formone cross-section.
Database handle for the object. It is of XML type ID, so is constrained to beunique in the XML document within which it occurs. An external identifier for the object inthe form of a URI may be constructed using standard XML and XPointer methods. This is doneby concatenating the URI for the document, a fragment separator, and the value of the idattribute.
Source
<element name="AbstractObservationGroup" type="diggs:AbstractObservationGroupType" substitutionGroup="diggs:AbstractProjectScopedGroup" abstract="true"><annotation><documentation>Abstract head of the substitution group for groups whose members are observation systems: ground models, logs and other interpreted characterizations. A member joins by carrying diggs:observationGroupRef, declared on diggs:AbstractObservationSystemType. No concrete type substitutes this head yet. Several observation systems may be meaningful only when read together, for example two ground models of the same site built on different assumptions, or logs that form one cross-section.</documentation></annotation></element>